/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.catalina.tribes.io;

import java.util.LinkedList;

/**
 * 
 * @author Filip Hanik
 * @version 1.0
 */
class BufferPool14Impl implements BufferPool.BufferPoolAPI {
	protected int maxSize;
	protected int size = 0;
	protected LinkedList queue = new LinkedList();

	public void setMaxSize(int bytes) {
		this.maxSize = bytes;
	}

	public synchronized int addAndGet(int val) {
		size = size + (val);
		return size;
	}

	public synchronized XByteBuffer getBuffer(int minSize, boolean discard) {
		XByteBuffer buffer = (XByteBuffer) (queue.size() > 0 ? queue.remove(0)
				: null);
		if (buffer != null)
			addAndGet(-buffer.getCapacity());
		if (buffer == null)
			buffer = new XByteBuffer(minSize, discard);
		else if (buffer.getCapacity() <= minSize)
			buffer.expand(minSize);
		buffer.setDiscard(discard);
		buffer.reset();
		return buffer;
	}

	public synchronized void returnBuffer(XByteBuffer buffer) {
		if ((size + buffer.getCapacity()) <= maxSize) {
			addAndGet(buffer.getCapacity());
			queue.add(buffer);
		}
	}

	public synchronized void clear() {
		queue.clear();
		size = 0;
	}

	public int getMaxSize() {
		return maxSize;
	}

}
